1. Field of the Invention
The present disclosure relates to an electronic device, an electronic system and a related method for processing signals from an audio accessory, and more particularly, to a device and method capable of executing corresponding functions on an electronic device by implementing a plurality of keys on an audio accessory without increasing extra pin(s) of the audio accessory.
2. Description of the Prior Art
Electronic devices equipped with multimedia playback functions, such as an mp3 player, a CD player, a mobile phone, or a personal digital assistant (PDA), are capable of playing audio signals anywhere. Generally speaking, such electronic devices include a specific audio output interface for outputting the audio signals to an audio playback device. For example, the mp3 player may include a 3.5 mm standard audio jack for outputting the audio signals to an audio output device such as a speaker or a headphone.
Please refer to FIG. 1 together with FIG. 2. FIG. 1 is a diagram showing a conventional audio plug 100 with three pins, and FIG. 2 is a diagram showing a conventional audio plug 200 with four pins. The audio plug 100 includes a first pin 110 for transmitting an L-channel signal, a second pin 120 for transmitting an R-channel signal and a third pin 130 coupled to a ground terminal. The audio plug 200 includes a first pin 210 for transmitting an L-channel signal, a second pin 220 for transmitting an R-channel signal, a third pin 230 coupled to a ground terminal, and a fourth pin 240 for transmitting an audio input signal (for example, a signal from a microphone). However, no matter whether the audio plug 100 or the audio plug 220 may be used, audio input functions and/or audio output functions may be supported, while other functions may not be achieved.